Because of the storage::Service's connection list, it's possible for the
refcount for a non-main-thread Connection to experience transient increases
and decreases at any time, dooming logic in Release() that assumes the
refcount isn't changing.
This patch adopts use of an Atomic<bool> so that we execute cleanup logic
exactly once when the refcount falls to 1 at some point. Care is taken to
ensure that the failsafe Close() occurs on the correct thread.
SpinningSynchronousClose() is still dangerous and can still potentially
nest deeply on the stack. If we see instances of that in the future, we
may want to adopt use of PushEventQueue so that we can avoid re-entrancy
in our event loop spinning.
MozReview-Commit-ID: A835HBec50H
--HG--
extra : rebase_source : af2f63e8f050b7a0275e39f73e59133958e29f19
cac42cb9b5